1. Field of the Invention
The present invention relates to an image processing method and apparatus that perform gradation matching between images formed by a first output unit and a second output unit which have different gradation reproduction ranges, and a recording medium used therewith.
2. Description of the Related Art
Conventionally, when a computer system, or the like, uses a printer to print an image displayed on a monitor, control of the lightness of an output image is performed using settings concerning lightness or an output gamma value in a printer driver. The printer driver corrects image data by using a gradation correction curve in accordance with set lightness or the output gamma value.
However, settings for the monitor cannot be reflected when the gradation correction curve for the printer is set. Also, the gradation correction curve for the printer is set without considering the relationship between a gradation correction curve outputable by the monitor and a gradation correction curve outputable by the printer.
Accordingly, these cause problems in that an image output by the printer is too bright or too dark than an image displayed on the monitor and in that part of the output image is too bright to be visible, or part of the output image is too dark for the gradation of the part to be perceptible.
In addition, conventionally, when the computer, or the like, uses the printer to print the image displayed on the monitor, control of the lightness or contrast of the image output by the printer is performed by changing lightness and contrast values in settings for the printer driver. The printer driver controls output lightness and contrast by using the set values to calculate the gradation correction curve, and correcting image data.
In the above conventional cases, regardless of gradation characteristics reproduced by the monitor, a gradation curve for output is set and output by lightness-change processing such as entirely brightening or darkening, or performing contrast-change processing such as increasing or reducing the inclination of the gradation curve.
Accordingly, this causes problems in that an image output by the printer is too bright or too dark,. and in that too dark portions, too bright portions, etc., appear.